[pgpool-general: 6764] Re: Watchdog does not get consensus for failover

[Muhammad Usama]

On Thu, Oct 31, 2019 at 7:50 AM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:

> >> Thanks. I confirmed that pgpool at proxy2 and proxy3 did not detect
> >> the failure of postgres1. So watchdog at proxy1 did not get
> >> consensus. I suspect the way you stopped postgres was something special
> >> (not ordinary shutdown by using pg_ctl). Can you elaborate how you
> >> stopped postgres1?
> >>
> >
> > I used "service postgresql stop" on postgres1. And then "start" to start
> it
> > again.
> >
> > So I have one question: why you ask me this? Does this mean that if
> > PostgreSQL would be killed in an "abnormal way" (like kernel hang, memory
> > or something else not made by user) the failover does not work?
>
> No, in these cases Pgpool-II's health check should detect the
> failure. I thought about the case a firewall was tweaked to block
> access from pgoool/proxy1 to PostgreSQL.
>
> Anyway, the debug log and "show pool_nodes" results look pretty
> strange since pgpool/proxy2 and pgpool/proxy3 thinks that PostgreSQL
> is healthy, while pgpool/proxy1 does not. For now I have no idea what
> could cause this situation.
>
>
Apparently from the log you shared, suggests that the health check never
detected the PG server failure
While the "failed to connect to PostgreS.." errors appearing on the standby
pgpool nodes are due to the
connection failure of the replication log checker that does not trigger a
failover.

Can you share the pgpool.conf files for all nodes. My suspicion is that the
health-check timeout values
are somewhat on the higher side, So that's why the  health-check might have
missed the unavailability of
PG server.

Best Regards
Muhammad Usama



> Best regards,
> --
> Tatsuo Ishii
> SRA OSS, Inc. Japan
> English: http://www.sraoss.co.jp/index_en.php
> Japanese:http://www.sraoss.co.jp
> _______________________________________________
> pgpool-general mailing list
> pgpool-general at pgpool.net
> http://www.pgpool.net/mailman/listinfo/pgpool-general
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.sraoss.jp/pipermail/pgpool-general/attachments/20191031/4022f4c2/attachment.html>